Make pseudo-classes selector queries work on DocumentFragment

Source/core/dom/ContainerNode.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 305 matching lines @@
         highest = node;
     return *highest;
 }
 
 inline ContainerNode* Node::parentElementOrShadowRoot() const
 {
     ContainerNode* parent = parentNode();
     return parent && (parent->isElementNode() || parent->isShadowRoot()) ? parent : 0;
 }
 
+inline ContainerNode* Node::parentElementOrDocumentFragment() const
+{
+    ContainerNode* parent = parentNode();
+    return parent && (parent->isElementNode() || parent->isDocumentFragment()) ? parent : 0;
+}
+
 // This constant controls how much buffer is initially allocated
 // for a Node Vector that is used to store child Nodes of a given Node.
 // FIXME: Optimize the value.
 const int initialNodeVectorSize = 11;
 typedef Vector<RefPtr<Node>, initialNodeVectorSize> NodeVector;
 
 inline void getChildNodes(Node& node, NodeVector& nodes)
 {
     ASSERT(!nodes.size());
     for (Node* child = node.firstChild(); child; child = child->nextSibling())
@@ skipping 61 matching lines @@
 
     RefPtr<Node> m_currentNode;
     unsigned m_currentIndex;
     OwnPtr<Vector<RefPtr<Node> > > m_childNodes; // Lazily instantiated.
     ChildNodesLazySnapshot* m_nextSnapshot;
 };
 
 } // namespace WebCore
 
 #endif // ContainerNode_h